Inspiratory muscle resistance combined with strength training: effects on aerobic capacity in artistic swimmers

Objective

This study aimed to investigate the effects of combining inspiratory muscle resistance with strength training on lung function and aerobic capacity in artistic swimmers.

Methods

This research constitutes a placebo-controlled randomized trial, involving a five-week walking program conducted twice a week. Fourteen female artistic swimmers were randomly assigned to either the experimental group (TG group, n = 7) or the control group (CG group, n = 7). Both groups underwent the same strength training program. The TG group performed inspiratory muscle strengthening at 50% of maximum inspiratory pressure (MIP) during strength training, whereas the CG group engaged in strength training with 15% MIP inspiratory muscle training twice a week. Pre- and post-intervention assessments included an incremental stress test, pulmonary function test, inspiratory muscle strength test, and a specialized performance test.

Results

Following the 5-week intervention, within-group comparisons revealed that the inspiratory muscle strength index, vital capacity, and forced vital capacity significantly increased in both the CG and TG groups (P < 0.01). The TG group exhibited a significant increase in minute ventilation (P < 0.05), while the CG group showed a significant increase in tidal volume (P < 0.05). Additionally, the TG group demonstrated a significant improvement in running speed at the ventilation threshold and maximum oxygen uptake (P < 0.05), along with a significant increase in tidal volume (P < 0.01). Both the CG and TG groups showed significant increases in the scores for the 50-meter diving and 25-meter torpedo (P < 0.05). Between-group comparisons showed that the TG group experienced significant improvements in the inspiratory muscle strength index, minute ventilation, running speed corresponding to maximum oxygen uptake, and 25-meter torpedo performance (P < 0.05).

Conclusion

The findings suggest that a 5-week program combining inspiratory muscle resistance with strength training can effectively enhance the aerobic exercise capacity of artistic swimmers. Moreover, high-intensity inspiratory muscle resistance combined with strength training can improve the muscle's ability to utilize oxygen during exercise.

Trial Registration

Beijing Research Institute of Sports Science (TKSLL202201); China Clinical Trial Registry, ChiCTR2300072833, 26/06/2023.

Effect of Chest Resistance and Expansion Exercises on Respiratory Muscle Strength, Lung Function, and Thoracic Excursion in Children with a Post-Operative Congenital Diaphragmatic Hernia

BACKGROUND

Congenital diaphragmatic hernia (CDH) is a life-threatening condition with long-term complications including respiratory tract infections, respiratory muscle weakness, and abnormal lung functions. This study was designed to ascertain the effects of chest resistance and chest expansion exercises on respiratory muscle strength, lung function, and chest mobility in children with post-operative CDH.

METHODS

This randomized controlled clinical study was conducted in the outpatient physiotherapy clinic at Prince Sattam bin Abdulaziz University. Thirty-two children with CDH aged 10-14 years between May 2020 and February 2021 were randomly allocated to the study group (n = 16) and the control group (n = 16). The control group underwent a usual chest physiotherapy program; however, the study group underwent a 12-week chest resistance exercise combined with chest expansion exercise in addition to usual chest physiotherapy, with three sessions per week. Respiratory muscle strength, lung function, and thoracic excursion were assessed pre- and post-treatment.

RESULTS

Using the 2 × 2 repeated ANOVA, significant time × group interactions were detected in favor of the study group, FVC (F = 4.82, 95% CI = -15.6 to -0.97, p = 0.005, and η² = 0.16), FEV1 (F = 4.54, 95% CI = -11.99 to -2.8, p ˂ 0.001, and η² = 0.14), PImax (F = 5.12, 95% CI = -15.71 to -5.3, p ˂ 0.001, and η² = 0.15), and thoracic excursion (F = 4.41, 95% CI = -2.04 to -0.16, p = 0.036, and η² = 0.17).

CONCLUSIONS

Concurrent chest resistance and expansion exercises may improve respiratory muscle strength, lung function, and thoracic excursion in children with post-operative CDH. The study findings suggest that concurrent chest and chest expansion exercises be part of an appropriate pulmonary rehabilitation program in children with a history of CDH.